Many people, at 80, feel ready to downsize their homes - but architect Bryan Thomas is still designing them.

Although he has just entered his ninth decade, he is still working four or five hours a day on a variety of projects for clients up and down East Anglia.

To him, ‘retirement’ is a stage of life he refuses to countenance.

Born the son of an engineer, Mr Thomas divided his early years between India, where he was born, and Felixstowe, Suffolk, where he attended prep school.

With family in Colchester and on Mersea Island, it was natural, after five years’ training, for him to move to the north Essex area in 1955, starting his practice two years later.

Private homes that started life on his drawing board in those early days were commissioned by Richard Wheeler, of Lay & Wheeler, the Colchester wine merchants, and the now-renowned plantswoman Beth Chatto at Elmstead Market.

“I helped her move her gingko tree on the back of a station wagon from Braiswick where she lived,” he recalled. “Of course, the gardens have grown so much over the years, that the only place you can see the house is from the gravel garden, which is how it should be.”

Mr Thomas’s schemes have been part of the Colchester skyline for 50 years now. And, although not large-scale buildings, they are of great importance to the people who visit, live or work in them.

They include Essex University’s health clinic and Wivenhoe House, also on the campus, where he added a 40-bed extension.

Showing the diversity of his work, he has designed both churches - St Andrew’s, Alresford, and Christ Church and the Friends’ Meeting House in Colchester - as well as rides and restaurants for Alton Towers and leisure industry complexes at Blackpool Pleasure Beach.

Then there were sheltered housing for the elderly and schools, including St Osyth Church of England Primary near Clacton.

“They all have their difficulties,” he explained. “It is quite a disciplined art, because it does have to incorporate financial limitations and those of the site, where the sun is and so on. Then there are the planners and any local objections. It can get quite hairy.”

Keen on light, unusual angles and shapes, Mr Thomas is naturally a fan of Colchester’s new betroubled arts venue.

“To be honest,” he said. “I think the visual arts facility is a breath of fresh air, because everything else that is being done has been so boring and dull.

“It was brilliant to have something new and fresh-thinking.

“The architect of the Sydney Opera House was fired when it was half finished. But what do you think of when you think of Australia? The Sydney Opera House. I think it could be the same for the Colchester visual arts facility.”

It is the architecture of another part of the world, which really inspires him. The Scandinavians’ penchant for wood drives many of his designs.

And he recognised, many years ahead of his time, the economic and ecological importance of insulating homes properly.

More than 60 years after he qualified, Mr Thomas, who lives with his wife Wendy in a 19th century house on Wivenhoe’s quayside, is still driven by ambition and challenge.

“I am very lucky, because I have a career that I can keep doing,” he said. “I do about 15 jobs a year, mostly from personal recommendation.

“I love challenges. If someone comes to me and says: ‘I have a real problem. We have thought about it for two years.’ That is the sort of thing I love.”

A family celebration marking his 80th birthday has been planned. But Mr Thomas is spending the actual day in London attending a talk at the Architectural Association on the architect, Le Corbusier, six decades after he, himself, was a student there.

And what of the future? In the short term, he is planning a retrospective of his long career. “I would like to have it at the visual arts facility,” he said. “But it could be at the Minories, where I did the extension.”

In the longer term, having built two family homes for himself in Alresford, he would love to build a third - a 21st-century eco-house. “But,” he said, looking out over the Colne, “Where would you find a plot like this on the river?”